Abstract
Plant-specific NAC proteins comprise one of the largest transcription factor families in plants and play important roles in plant development and the stress response. Gossypium hirsutum L. is a major source of fiber, but its growth and productivity are limited by many biotic and abiotic stresses. In this study, the NAC domain gene GhNAC79 was functionally characterized in detail, and according to information about the cotton genome sequences, it was located on scaffold42.1, containing three exons and two introns. Promoter analysis indicated that the GhNAC79 promoter contained both basic and stress-related elements, and it was especially expressed in the cotyledon of Arabidopsis. A transactivation assay in yeast demonstrated that GhNAC79 was a transcription activator, and its activation domain was located at its C-terminus. The results of qRT-PCR proved that GhNAC79 was preferentially expressed at later stages of cotyledon and fiber development, and it showed high sensitivity to ethylene and meJA treatments. Overexpression of GhNAC79 resulted in an early flowering phenotype in Arabidopsis, and it also improved drought tolerance in both Arabidopsis and cotton. Furthermore, VIGS-induced silencing of GhNAC79 in cotton led to a drought-sensitive phenotype. In summary, GhNAC79 positively regulates drought stress, and it also responds to ethylene and meJA treatments, making it a candidate gene for stress studies in cotton.
Highlights
As a major source of fiber, cotton (Gossypium hirsutum L.) shows greater tolerance to drought and salt than wheat and rice, but with the changing of global climate and increasing level of pollution, abiotic stress is becoming a major limiting factor for cotton growth and productivity (Ahuja et al, 2010)
GhNAC79 belongs to the NAM subfamily, many members of which are involved in plant development; for example, AT2G17040.1/ANAC036 are associated with a dwarf phenotype and distorted leaves in Arabidopsis (Kato et al, 2010)
Drought is always associated with ABA (Li C. et al, 2015; Tombesi et al, 2015; Yin et al, 2015), so we explored the relationship between GhNAC79 and ABA
Summary
As a major source of fiber, cotton (Gossypium hirsutum L.) shows greater tolerance to drought and salt than wheat and rice, but with the changing of global climate and increasing level of pollution, abiotic stress is becoming a major limiting factor for cotton growth and productivity (Ahuja et al, 2010). Among these factors, high salinity and drought are the main stresses (Wang et al, 2001; Rabbani et al, 2003); currently, more than 10% of arable land is experiencing water shortages, leading to a 50% average reduction in the yield of major crops (Bartels and Sunkar, 2005). Improving stress tolerance and delaying leaf senescence in cotton through genetic engineering is a promising production strategy for which candidate genes need to be identified.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
